a) Field of the Invention
The present invention relates to a fire-resistant glass comprising at least two plate-shaped vitreous materials arranged parallel and apart, a spacer provided between the plate-shaped vitreous materials at their peripheries, and an aqueous gel filled into the space formed by the plate-shaped vitreous materials and the spacer, as well as to a process for production of said fire-resistant glass.
b) Description of the Related Art
A composite material is disclosed in Japanese Patent Publication No. 24063/1985, which material comprises two parallel glass plates and an aqueous gel containing a polymer of an acrylic acid derivative and a soluble and foamable salt (e.g. water-glass), interposed between the glass plates. Since the soluble and foamable salt contained in the gel is strongly alkaline, said composite material needs careful handling; the acrylic acid derivative polymer contained in the gel may undergo easy deterioration; and the gel-supporting material may be corroded depending upon the type. Further, since the soluble and foamable salt generally has a low melting point and insufficient high-temperature stability, the salt is easily melted in contact with flames.